手持式颈椎椎弓根螺钉置钉瞄准器的研制及意义

Study on the manual aiming device for the cervical pedicle screw placement and its clinical significance

目的:研制能三维调节角度的手持式置钉瞄准器,为颈椎椎弓根螺钉置钉提供帮助。方法:制作以杠杆百分表显示偏摆角度的瞄准器,利用图形矢量化软件快速处理术前轴位CT图和45°斜位X线片,精确确定进钉点、置入角度、螺钉直径与长度,推导出椎弓根术前影像学数据与瞄准器钻套调整角的关系公式,采用正弦规校验瞄准器钻套调整角。以瞄准器为钻模在9具新鲜成人标本颈椎椎弓根上进行钻孔,并进行个体化置钉。结果:共置入椎弓根螺钉46枚,42枚位置正确,正确率为91%。结论:手持式颈椎椎弓根螺钉置钉瞄准器可提高置钉的准确性和安全性,有临床应用前景。

Objective：In order to assist doctors in operation of the cervical pedicle screw placement,manual aiming device which can be modulated at the three dimensions according to the angles of the cervical pedicles was studied.Method：The aiming device was designed as its angles could be displayed by lever-dial indicator.Software of graph vectorization was applied to handle the pre-operative images of CT scan and X-ray films of 45° oblique view of cervical pedicle,so the screws-entry positions,entry angles,diameter and length were able to be accurately determined.The relationship between the measurements of pre-operative pictures and the angles of drilling ringers of aiming device was deduced.Sine dividers was used to test the angles of drilling ringers finally.Screws were inserted in cervical pedicles of 9 fresh adult samples,aiming device was used individually as drilling jig during operation.Restdt：42 of 46 screws were in correct position,correction rate was 91%.Conclusion：Using the manual aiming device for the cervical pedicle for screw placement can improve the accuracy and safety during operation,and this device can be applied and popularized clinically.